Liveness probe concept in Kubernetes - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a liveness probe in Kubernetes?

A liveness probe is a check Kubernetes uses to see if a container is still running and healthy. If the probe fails, Kubernetes restarts the container to fix it.

beginner

How does Kubernetes react when a liveness probe fails?

Kubernetes restarts the container to try to fix the problem when the liveness probe fails.

intermediate

Name three types of liveness probes supported by Kubernetes.

Kubernetes supports HTTP GET requests, TCP socket checks, and running a command inside the container as liveness probes.

intermediate

Why is it important to set the initial delay for a liveness probe?

Initial delay lets the container start up fully before Kubernetes starts checking its health, preventing false restarts.

intermediate

What is the difference between a liveness probe and a readiness probe?

A liveness probe checks if the container should be restarted, while a readiness probe checks if the container is ready to accept traffic.

What happens if a liveness probe fails in Kubernetes?

A The pod is scaled up

B The container is restarted

C Nothing happens

D The container is deleted permanently

When a liveness probe fails, Kubernetes restarts the container to recover it.

Which of these is NOT a type of liveness probe?

A Memory usage check

B TCP socket check

C HTTP GET request

D Running a command

Memory usage check is not a built-in liveness probe type in Kubernetes.

Why do we use an initial delay in liveness probes?

A To disable the probe

B To delay container startup

C To speed up restarts

D To wait before starting health checks

Initial delay waits before starting health checks to avoid false failures during startup.

Which Kubernetes object uses liveness probes?

A Service

B ConfigMap

C Pod

D Namespace

Liveness probes are configured on containers inside Pods.

What is the main goal of a liveness probe?

A To check if the container is alive and restart if not

B To check if the container is ready to serve traffic

C To monitor network traffic

D To update container images

Liveness probes check if the container is alive and restart it if it is not.

Explain what a liveness probe is and why it is useful in Kubernetes.

Think about how Kubernetes keeps containers running smoothly.

Describe the different types of liveness probes and when you might use each.

Consider how you can check container health in different ways.